Soil stabilization and foundation restoration using an expandable polyurethane resin

Grounds and foundations, underground structures

The settlement of foundation is one of the main existing problems which face construction engineers during the construction operation processes since the design of a project and through the whole construction life and it leads to bad consequences on the construction. Many methods have been implemented during the last decades to stabilize the soil, lift basements and reduce further settlements. Some of these methods are actively used and effective while others are less effective, have limitations of uses and/or expensive methods. Soil injection technology using an expandable polyurethane resin is an innovative technology which offers an efficient solution for the construction settlements and leads to the stabilization of the soil. The paper demonstrates the results of a full-scale experiment which was implemented in-situ to investigate the effect of the soil injection technology on the lifting of a concrete foundation and on the stiffness of the soil beneath the foundation (soil stabilization) at different soil depths. Dynamic cone penetration test DCPT was applied before and after the injection of the expandable resin in two different plots, one of the plots was injected (the soil has been treated) and the second plot considered as a reference plot where no injection was carried out (with no soil treatment). Results of the soil investigations before and after the injection of the expandable resin are achieved and analyzed. The graphs of DCPT before and after the injection process in different comparison points are incorporated and compared to the geological report of the investigated area. The injection process is explained, and the foundation lifting to the desired level is achieved and explored in this article.